Homogeneous piled surface



July 20, 1937. L; x5.- MILLER Y 2,087,260 4 HouoanNEous PILED SURFACEFilled April 18, 1935 Vfl-wb i Wwf SW' Patented July 20, 1937 PATENTOFFICE 2,087,260 HOMOGENOUS FILED SURFACE Louis P. Miller, Brooklyn, N.Y., assigner to Research Corporation, New York, N. Y., a corporation ofNew York Application April 18, 1935, Serial No. 17,126

13 Claims. (Cl. 91-68) This invention. relates to piles and piled sur-ffaces and their manufacture, and is directed particularly to a pilecomprising attenuated elements and an indurated binding substance withwhich they are combined into a homogeneous structure,

C and to a method of making the same.

I'he invention is especially valuable when it is included in the methodof piling surfaces comprising: coating the surface to be piled withadhesive, placing the coated surface in an electric field, and supplyingfibers or other pile forming elements to the region of the electricileld, that they may be oriented and deposited on the adhesive coveredsurface by the action onthe l5 electric field.

'Ihe principal object of the invention is to form a pile of attenuatedparticles, such as rayon .fibers or flocks, wherein one end of eachfiber is incorporated into an indurated material and makes a homogeneousstructure with it.v

Another object of the invention is to incorporate one end of each of agroup of fibers into an induratable binding material to form a pile bythe use of a. solvent common to fibers and bind- 111g material. V

Another object of the invention is to so control the softening action ofa solvent included in an induratable binding material o'n the bers to beattached thereto in the forming of a pile that one end of each ber willbe amalgamated with the binding material to make a common substance withit.

A specific object of the invention is to make a l pile of cellulosederivative fibers by fastening one end of each fiber into the pilestructure with an adhesive, including a volatile solvent for thecellulose derivative, such as acetone, and then driving out the solventand indurating the adhesive.

40 A further specific object ls the production of a pile of attenuatedelements upon a surface by coating the surface with an adhesiveincluding a solvent for the elements, orienting the elements andprojecting them endwise with an electric field into the adhesive,holding them in oriented position until the solvent has softened theimbedded ends of the elements and incorporated them into the adhesive tomake a homogeneous structure with it, and then indurating the adhesive.

The products obtained from a. realization of the above objects and suchother objects as will be pointed out in the following exposition arecharacterized by the strong attachment between the individual fibers orelements and the common binding material. When very ine bers, such asrayon flocks, are projected endwise, fori` instance under the influenceo f an electric field. into an. adhesive, they do not penetrate deeply,as a rule, and are not always wetted sulilciently by an 5 ordinaryadhesive to produce a strong bond between adhesive and liber. The resultis a pile with an appreciable number of elements which will becomedislodged when the pile is brushed or given otherA rigorous handling. Anadhesive l0 with a constituent that is a. solvent for the bers,

on the other hand, definitely wets, and partially dissolves, each fiberthat contacts it for any length of time, and the result is a blending orincorporating of fibers and adhesive into a homol5 geneous whole. Uponevaporation of the solvent or solvents and induration `of the adhesive avery strongly bonded pile results.

In the following description of the invention reference is hadto theappended drawingin 20 which:

Fig. 1 is a diagrammatic view, in side elevation, of apparatus useful inpracticing the method of the invention; and

Fig. 2 is a fragmentary cross-sectional view 25 of the product made withthe apparatus shown in Fig. 1 taken on line 2-2 of that figure.

In Fig. 1, numeral I'identiles a 'sheet material, for example, a sheetof closely woven cloth, a surface of which is to be piled. Sheet I ismoved 30 over rolls 2 and 3 in the direction indicated and in doing sopasses under electrode 4 which is insulated from ground and maintainedat a high potential with respect to ground by connecting it to a source(not shown) of high voltage, prefer- 35 ably unidirectional, current byconductor 5. A suitable adhesive is applied to the under surface ofsheet I by rolls 6 and 1 in the manner readily appreciated by thosefamiliar with the coating art. The aidhesive'is held in container 8,which 40 has a close fitting top, except for the projecting area of roll6, to minimize the losses of solvent by evaporation.

The attenuated elements, such as textile fibers, used in building` thepile are distributed by means 45 9 upon belt II) moving over rolls IIand I 2. Belt III- may be of metal and held at ground potential, or itmay be of semi-conducting or insulating material, in which case it ispassed over an electrode I3, grounded at I4. In either 5o case a strongelectric eld that terminates on electrode 4 exists adjacent the top ofbelt I0; and this electric field, which can be considered. as existingbetween electrodes 4 and I3, lifts the fibers from the surface of beltI0 and de- 55 =posits than nlv surment sheets. in

'onendposiuon to tiatfsurfa. Sheet Imoves at a 'ratewhich permits-thepile to form lwith the density. After deposition-.the piled sin-faceismoved-tmoughla neating chamber I5, I5' containing electricalheating`elements I6 and I 'I wherein the solvents are driven from the adhesive,to be collected for reuse if economically advisable, and the adhesivehardened to the desired degree.

The several stepsrecommended in electrically depositing fibers aredisclosed in detail` in U. S. patent applications Serial' No. 692,201,of A. F. Meston led October 4, 1933, and Serial No. 699,456, of H. F.Wintermute illed Nov. 23, 1933.

Fig. 2 shows a portion of the product of the invention in which fabric2I corresponds to sheet lsubstance had been distributed which had asolvent or softening effect upon bers 23. 'I'he solvent softened orpartially dissolved the ends of the fibers projecting into or contactingthe adhesive and broughtabout an intimate associationy of the materialscomprising bers and adhesive as. shown at 24, with the result that upondriving out the solvent and indurating the adhesive the fibers wereautogenously welded to the binding'materlal'in what may be termed ahomogeneous whole. i

I have obtained very satisfactory results with a solvent common to bothbinding material and bers. For example, in depositing cellulose acetaterayon fibers, I have used acetone in an adhesive composition comprisingcellulose acetate, a relatively high boiling point solvent, such asethylene glycol mono-methyl ether (Cel1o solve) and a plasticizer.Deposition with this combination under conditions which controlled theevaporation of the acetone and the surface penetrativeness of theadhesive have produced piles with very strongly attached bers. Thedeposition apparatus is preferably enclosed in a chamber when a highlyvolatile solvent, such as acetone, is used and it has bee'n foundadvisable to control the gaseous contents of the chamber as totemperature and other vapor pressure conditions and to guard againstpossible explotion.

Other llulose derivatives, such as the esters and ethers of cellulose,as well as other iibrous substances capable'of being dissolved orsoftened by an ingredient od.' the adhesive composition, may be used inplace of cellulose acetate.

While the invention has been particularly described for the purpose ofillustration in connection with the production of a product including afabric backing, other backings, such as sheets of preformed induratedmaterial, may be used, orv the bers may be deposited; on a layer ofadhesive on a temporary backing. being later removed from the temporarybacking and used as such or applied to a permanent backing.

It will be appreciated bythose familiar with the characteristics ofadhesives and textile and other flbers'that many embodiments of myinvention are possible. What I wish to emphasize as the-broad conceptionof the invention is the adsense breaking oi-y the surface of theberwhere I claim: j

1. A method of making pi1e-surfaced.mate' rial. which comprisesdepositing attenuated bers of a cellulosic derivative in a layer of anadhe-` 2. A method of making pile-surfaced materialv which comprisesdepositing attenuated bers of a cellulose ester in a layer of anadhesive composition including a substance having a solvent actiononsaid cellulose ester, and indurating the adhesive layer.

3. A method of making pile-surfaced material which comprises depositingattenuated bers of cellulose acetate in a layer of an adhesivecomposition including a substance having a solvent action on saidcellulose acetate, and indurating the adhesive layer. I

4. A method of making pile-surfaced material which comprises depositingattenuated fibers of a cellulosic derivative in a layer of an 'adhesivecomposition including a similar cellulosic derivative and a substancehaving a solvent action on said cellulosic derivative, and induratingthe adhesive layer.

5. A method of making pile-surfaced material which comprises depositingattenuated bers of a cellulosic derivative in a layer of an adhesivecomposition including cellulose acetate and a substance having a solventaction on-said cellulosic derivative, and indurating the adhesive layer.

6. A method of making pile-surfaced material which comprises forming alayer of an adhesive composition comprising a cellulosic derivative, avolatile solvent therefor, a high boiling solvent, and a plasticizer,depositing thereon attenuated fibers of a similar cellulosic derivativeand indurating the adhesive layer by removing the volatile solvent.

7. A method of making a pile-surfaced material which comprises forming alayer of an adhe-y sive composition comprising cellulose acetate,acetone ethylene glycol mono-methyl ether and a plasticizer, depositingthereon attenuated fibers of cellulose acetate and indurating theadhesive layer by removing the acetone. l

8. A pile-surfaced sheet material comprising a layer of induratedadhesive substance and a pile consisting of attenuated bers embedded atone end in said layer and physically homogeneous therewith. f

9. A pile-surfaced sheet material comprising a layer of induratedadhesive substance and a pile consisting of attenuated bers embedded atone end in said layer and physically and chemically homogeneoustherewith.

10. A pile-surfaced sheet material comprising a layer of induratedcellulosic substance and a pile consisting of attenuated fibers of acellulose derivative embedded at one end in said layer and physicallyhomogeneous therewith.

11. A pile-surfaced sheet material comprising a, layery of induratedplastic composition including cellulose acetate and apile consisting ofattenuated fibers of cellulose acetate embedded at one end in said layerand physically homogeneous therewith.

.it eontsctstnebindingimaterai-so that the den: l `nite interface which-'.separates two s uch substances is, -to -an appreciable `degree;eliminated and 'the fiber. becomes -integrally .united wlththe bindingmaterial.`

12. A pile-surfaced sheet material comprising a. backing, a layer ofindurated adhesive substance thereon and a. pile consisting ofattenuated bers embedded at one end in said layer 5 and physicallyhomogeneous therewith.

13. A pile-surfaced sheet material comprising a backing, a layer ofindurated plastic composition including cellulose acetate thereon and apile consisting of attenuated bers of cellulose acetate embedded at oneend in said layer and physically homogeneous therewith.

LOUIS P. LULLER.

